HVAC lateral condensate drain channel

Abstract

The present invention relates to HVAC units with condensate drainage systems, for use in motorized vehicles. The present invention provides for at least two or dual condensate drain paths with no extra parts required pre-distribution of the treated air from the HVAC unit, the drainage means or channel situated to allow condensate to ‘fall back’ or, to run upstream back from the evaporator in the opposite direction to the air in the main airflow or stream which continues to run downstream from the drainage area to be conditioned by the heat exchanger.

Description

FIELD OF THE INVENTION [0001] The present invention relates to the field of HVAC units that form condensate during normal operations, and, particularly, HVAC units with condensate drainage systems, for use in motorized vehicles. BACKGROUND OF THE INVENTION [0002] In HVAC units, heat exchangers, due to changing temperature and other conditions within an essentially closed environment, end up forming condensate from the air inputted into the HVAC unit. It is undesirable for excess humidity or condensate to remain in the HVAC unit, or to be distributed downstream of the heat exchangers after the air is conditioned in the unit to the outside areas, such as the passenger and other motor vehicle compartments. [0003] In prior art HVAC unit, this undesirable condensate has often been drained from the area of the heat exchanger, such as an evaporator, by exhausting and / or evacuating the condensate from areas beneath the evaporator via a separate or ‘segregated’ channel which is found away fr...

AI Technical Summary

Benefits of technology

[0005] The present invention, therefore, allows for drainage of condensate (such as water or other fluids in the incoming airstream, that normally enter the HVAC outside of the HVAC unit itself, to be exhausted. The present invention provides for at least two condensate drain paths with no extra parts required pre distribution of the treated air from the HVAC unit. In preferred embodiments of the present invention, the drainage means or channel is situated to allow condensate to ‘fall back’ or, to run upstream back from the evaporator in the opposite direction to the air in the main airflow or stream which continues to run downstream from the drainage area to be conditioned by the heat exchanger, and, more preferably, from the evaporator. This provides for air in the outflow region directly downstream from the evaporator to be shedded of its condensate should the need arise, and still allow drainage of the condensate, without entrainment of the condensate back into the airflow so that it would eventually get to the distribution system downstream of the HVAC unit itself. Advantageously, the present invention allows for both the air propulsion means (e.g. blower) and the heat exchanger, and, preferable, the evaporator, to be positioned at approximately the same level vertically in space, i.e. at approximately the same height at the base of each, so that, if one is slightly higher, (for example, a 10% difference in level or on the same plane horizontal to the ground in normal operating position of the vehicle), it will still operate, while preventing any backflow of condensate or water, under nearly all vehicle parking orientations, in the air that might otherwise be in or downstream of the drainage area, to reach upstream areas like the blower or the area immediately downstream from the blower.

[0007] In particularly preferred embodiments of the present invention, tooling is simplified due to its dual path drainage. Condensate, since it does not stagnate or collect in unwanted areas, does not create unwanted odor formation or other related undesirable effects related to condensate retention. In more preferred embodiments, condensate for the airstream drains not only from directly under the evaporator, but also before evaporator, through the same mechanism. In even more particularly preferred embodiments, condensation that forms or collects at all locations prior to reaching the heat exchanger, and, in particular, the evaporator region, flows to the same area and, preferably, through the same drainage channel, even more preferably, a U shaped drainage channel. The impact on noise is minimal to non-existent in preferred embodiments of the present invention. By preventing condensate from ‘flowing back’ into the blower area once it has passed the region of the upstream edge of the U drain, even during heavy accelerations, the present invention allows for the maximum of condensate free air to reach the distribution area for delivery outside of the HVAC unit.

Problems solved by technology

In prior art HVAC units, water is often blown back under the evaporator pan or drainage area during normal operations.

Separate or segregated paths or ‘dual paths’, one for the condensate drain and one for the air flow, has meant increased tooling complexity and other manufacturing difficulties.

In addition to cost issues, problems with quality and tool maintenance are intensified due to this dual path system.

The dual path systems have also led to addition problems, particularly since in areas at or near the base of the evaporator, where the airflow means that moving air directly contacts that portion of the evaporator, either slots or slopes are required to allow water to pass through with the drain airstream into a drain pan under the evaporator itself.

Such an architecture has been required to prevent water from ‘pooling’ or otherwise being formed and remaining upstream of the evaporator, allowing such pooled water to stagnate or remain and cause additional problems such as development of odor or microbial growth in the unit.

An additional problem from the commercial standpoint rests in the fact that ‘pooled’ or ‘stagnant’ condensate upstream of the evaporator can later flow backward into the area of the blower at blower speeds and / or during vehicle maneuveuring or parking below a certain level, causing eventual electro-mechanical warranty problems for such units.

Images